Solution :
Given that,
= 0.5
1 - = 1 - 0.5 = 0.5
margin of error = E = 0.034
At 90% confidence level z
= 1 - 90%
= 1 - 0.90 =0.10
/2
= 0.05
Z/2
= Z0.05 = 1.645
Sample size = n = (Z/2 / E)2 * * (1 - )
= (1.645 / 0.034)2 * 0.5 * 0.5
n=585
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